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Offline Flyingraptor

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Re: When do you stop to fill up? (how to read gas gauge)
Reply #10 on: June 08, 2021, 09:02:26 AM
I always wait until the last bar on the fuel gauge starts flashing. I fill the tank fully, with on average 14 L (3.7 US Gallon). So typically there are about 3 L (0.8 US Gallon) left in the tank when I stop for fuel.

PS: I am always astonished about the mileages I read here. My average mileage is 6.41 L/100 km (about 36.69 MPG). And I don't ride like a lunatic (I think  :008:). My trips are usually short though, maybe that differs from typical riding in the US?

Offline Frontline

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Re: When do you stop to fill up? (how to read gas gauge)
Reply #11 on: June 08, 2021, 12:00:00 PM
*Originally Posted by Flyingraptor [+]
PS: I am always astonished about the mileages I read here. My average mileage is 6.41 L/100 km (about 36.69 MPG). And I don't ride like a lunatic (I think  :008:). My trips are usually short though, maybe that differs from typical riding in the US?
For the record, I've found the dash "average mpg" to not be as accurate as actually logging mileage and fill ups. So I only measure mine by my actual mileage and actual gas I put in (ie. calculator at fill up).

What everyone needs to remember is your actual mileage isn't accurate and you need to subtract about 6% of the indicated mileage.
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Offline Flyingraptor

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Re: When do you stop to fill up? (how to read gas gauge)
Reply #12 on: June 08, 2021, 12:16:43 PM
*Originally Posted by Frontline [+]
For the record, I've found the dash "average mpg" to not be as accurate as actually logging mileage and fill ups. So I only measure mine by my actual mileage and actual gas I put in (ie. calculator at fill up).

What everyone needs to remember is your actual mileage isn't accurate and you need to subtract about 6% of the indicated mileage.

Thanks for the info. The numbers I mentioned were actual loggings, not based on the info provided by the dash.  :002:

Offline Its about speed

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Re: When do you stop to fill up? (how to read gas gauge)
Reply #13 on: June 08, 2021, 04:47:57 PM
*Originally Posted by Frontline [+]
For the record, I've found the dash "average mpg" to not be as accurate as actually logging mileage and fill ups. So I only measure mine by my actual mileage and actual gas I put in (ie. calculator at fill up).

What everyone needs to remember is your actual mileage isn't accurate and you need to subtract about 6% of the indicated mileage.


Yeah for sure on that.  My actual speed by GPS is slower than the dash speedometer.

All of my numbers are off the dash. Estimates.

I wonder if we've confused Balbino yet?

If in doubt, don't run out.



Offline Z900-WA

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Re: When do you stop to fill up? (how to read gas gauge)
Reply #14 on: June 10, 2021, 01:59:44 AM
I pretty much always ride pretty aggressively & gotta say 30ish - 35mpg isn't very impressive. Especially when I ride w my friends on their FZ-09's. Riding at pace they both get 45+mpg. Thankfully the Z's got a bigger tank tho.

That said, highway cruising is capable of 40-45ish mpg. Not common riding for me tho.

Lastly, here's what's really bizarre imo...

Been practicing my wheelie skills a lot lately & w quickshifter I can stay up thru 4th gear, sometimes even for a half mile or more (& ya, I'm pretty damn proud of it too) 😉

What's strange tho, is that when I do spend a few hours practicing, I gotta fill up afterwards & my mpg is like 15. Pretty sure that balance point on the Z causes fuel to to exit thru drain hose. If anyone has a fix for or even an explanation for this I'd be really interested to know what's happening. Thanks ✌

Offline porkchop

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Re: When do you stop to fill up? (how to read gas gauge)
Reply #15 on: June 10, 2021, 06:10:17 PM
*Originally Posted by Z900-WA [+]
What's strange tho, is that when I do spend a few hours practicing, I gotta fill up afterwards & my mpg is like 15. Pretty sure that balance point on the Z causes fuel to to exit thru drain hose. If anyone has a fix for or even an explanation for this I'd be really interested to know what's happening. Thanks ✌

There isn't a drain hose, it's a vent.
Highly doubt you're standing the bike up at a enough vertical position to lose that much fuel thru it- if you did you'd notice it dripping alot.
Likely the gear / higher RPMs screaming and such to get it up is using it more than just maintaining one constant street speed + having the ECO light come on.
Messing around, burn more fuel.
"The ride is the reason"

Offline KawaJagz

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Re: When do you stop to fill up? (how to read gas gauge)
Reply #16 on: June 10, 2021, 09:01:48 PM
*Originally Posted by Z900-WA [+]
I pretty much always ride pretty aggressively & gotta say 30ish - 35mpg isn't very impressive. Especially when I ride w my friends on their FZ-09's. Riding at pace they both get 45+mpg. Thankfully the Z's got a bigger tank tho.

That said, highway cruising is capable of 40-45ish mpg. Not common riding for me tho.

Lastly, here's what's really bizarre imo...

Been practicing my wheelie skills a lot lately & w quickshifter I can stay up thru 4th gear, sometimes even for a half mile or more (& ya, I'm pretty damn proud of it too) 😉

What's strange tho, is that when I do spend a few hours practicing, I gotta fill up afterwards & my mpg is like 15. Pretty sure that balance point on the Z causes fuel to to exit thru drain hose. If anyone has a fix for or even an explanation for this I'd be really interested to know what's happening. Thanks ✌

Try keeping both wheels on the ground and the revs below 4k 😂
I used to be indecisive, but now I'm not so sure!

Offline Z900-WA

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Re: When do you stop to fill up? (how to read gas gauge)
Reply #17 on: June 11, 2021, 01:05:58 AM
*Originally Posted by porkchop [+]
There isn't a drain hose, it's a vent.
Highly doubt you're standing the bike up at a enough vertical position to lose that much fuel thru it- if you did you'd notice it dripping alot.
Likely the gear / higher RPMs screaming and such to get it up is using it more than just maintaining one constant street speed + having the ECO light come on.
Messing around, burn more fuel.

 I'm sure that's a possibility but it is a pretty drastic variance given I pretty much never just cruise around at low rpm's in general. I'm on baron backroads riding hard 90% of the time when I'm not working on my wheelie skills. I'm def gonna keep an eye out for fuel on pavement in my primary practice spot tho. Cuz I'm thinking this means there is a drain hose for fuel based on the service manual & the Multiple hoses I noticed near the front sprocket last time I checked (a while back & didn't trace the lines, just assumed one was for fuel).

Appreciate the response tho. I'll follow up if I do get to the bottom of it.

For the time being the fun & skill-building is more than worth a few extra bucks in fuel 🙌


Offline Timevoid

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Re: When do you stop to fill up? (how to read gas gauge)
Reply #18 on: June 11, 2021, 09:54:22 AM
I don't to be negative but i stopped for fueling when i had 1 bar left. And i could only fill around 11 liters /2.9Gallon .
Then its 6 Liters/1.6 gallons left in tank. So at 1 bar i got like 1/3 tank left.  i think its 6 bars right. Its very inaccurate as most fuel gauge.

I can ride almost 110km/ 68 miles on that fuel of 1 bar fuel gauge. 

So for now i will set the trip meter instead. I know i can get at least 310km/ 192 miles from riding quite aggressive.  So trip meter and "Range" gauge i think is better way then getting nervous stare at the fuel gauge all the time 

Riding 90km/h / 56 mph i think the fuel economy is super low. Fuel-consumption about 0,4 / 10km ( 6miles / 0.1gallon) .

Last Edit: June 11, 2021, 09:57:31 AM by Timevoid

Offline Frontline

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Re: When do you stop to fill up? (how to read gas gauge)
Reply #19 on: June 11, 2021, 12:27:41 PM
Okay, time to explain why some people show slightly different results (miles to empty)....The really boring stuff  :139:

*Obviously, terrain plays a huge part of that but I'm only discussing how the tank functions or the components that measure it work

As typically found in almost all fuel tanks on the planet, the Z900 uses a very basic fuel float in conjunction with a variable resistor. Resistance increases with less fuel and decreases with more fuel - 2200% delta!. Resistance can also vary with temperature (basic ohms law). Plus there's a margin of error when full and when empty. In the case of the Z900, its 2.8 ohms when full and 6 ohms when empty. The electronics that relay (pun) that input to something a human can read (the actual display on dash) have a very wide buffer so you don't see fuel levels go up down while fuel is sloshing in tank (like cars from the 60's and 70's did). But at end of day, its just a basic form of measurement that can vary with temperature, age, angle/bend of float arm, and actual resistor tolerance. Not only that, but the potentiometer isn't always linear from full to empty. Basic design but has been a proven method and done this way for well over 60 years. So the "miles to empty" is going to be different. The fact it works as well as it does, always impress me. So next time you stare at your fuel level, you get an insight of what goes through my mind  :125:

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